Major Haskell packages overhaul.

Several changes, some highlights:

  * Structure of haskell-packages.nix updated. It's now easier to
    select different default versions of packages for different
    versions of GHC.

  * GHC 7.0.2 is now default.

  * Haskell Platform 2011.2.0.0 has been added and is now default.

  * Several packages have been updated
    (gtk2hs, gitit, xmonad, darcs, ...).

  * Some old packages have been removed.

svn path=/nixpkgs/trunk/; revision=26288

pkgs/development/libraries/haskell/parsec/3.1.1.nix

@@ -2,8 +2,8 @@
 
 cabal.mkDerivation (self : {
   pname = "parsec";
-  version = "3.1.0";
-  sha256 = "962d39944bae18b0fea60961c77513f455f95c0f67ae4b10ab15484a27b6fb98";
+  version = "3.1.1"; # Haskell Platform 2011.2.0.0
+  sha256 = "0x34gwn9k68h69c3hw7yaah6zpdwq8hvqss27f3n4n4cp7dh81fk";
   propagatedBuildInputs = [mtl];
   meta = {
     license = "BSD";